BACKGROUND & OBJECTIVE
Rotation is an extremely important movement of the spine. Approxiamtely 80% of spinal rotation comes from the thoracic spine. Limitations associated with spinal rotation are often related to injuries not only in the thoracic spine itself, but in many other areas of the body. To date, a number of measurement based approaches have been documented for assessing thoracic spine rotation, but most require expensive equipment, have poor validity and are difficult to use in clinical practice. Therefore, this study aimed to assess the validity of the digital inclinometer and iPhone for measuring thoracic spine rotation.
This study included 23 participants aged 19 to 34. They exluded participants if they had spinal problems in the previous 12 months before the study. Three different devices were used to measure thoracic rotation - ultrasound image (reference standard), a digital inclinometer and an iPhone programmed with the 'clinometer' app. An experienced musculoskeletal physiotherapist performed the measurement of thoracic rotation in the heel-sit position with each of these three devices.
The iPhone and digital inclinometer both demonstrated strong criterion validity compared with the reference standard (r=0.88,P < .001 for both). The mean difference between the iPhone reference standard measurement angle was 4.94° (95% CI = 19.23°,-9.35%°), and the digital inclinometer